Laser is a much better print technology thank inkjet. Only bother with inkjet if you need a brand new printer for $30 or you frequently need detailed color prints. Even then, I ended up with a color laser and it was going to be much cheaper per page over the life of the printer than any inkjet would be. I don't know if that has changed in the modern time now that we have stuff like big-tank and explicitly refillable inkjet printers.
The trade-off is that, especially older lasers are big and take a lot of energy. They take longer to get warmed up if you leave them switched off but they typically print faster than inkjet and so you definitely make up your time if you print often or if you print larger jobs.
There are cheap, plentiful laser printers from the last 20 years that'll talk the Apples over Ethernet (Ethertalk) which can be adapted to older Macs with Ethertalk/Localtalk bridges (which I consider to be an important tool for networking anyway) and of course will be able to talk to a 9600 directly over Ethernet.
I got a Xerox Phaser 6120EN back in ~2006. I don't remember if there was a dedicated PPD for it, but you can point the Laserwriter 8 driver on shstem 7 or newer at it and say "that's an apple color laserwriter" or "that's an hp color laserjet" and it works great. I also have some friends who bought less expensive monochrome lasers. You can tell a Mac that something like a Brother HL2070N is a laserwriter 16/600 or so and it should work. I don't remember if these printers included dedicated PPDs that worked on OS 9, but you don't strictly speaking need it for simple print jobs on PostScript printers.
There's also older HP LaserJets. LaserJets 4M and 5M will probably live longer than you will, a couple companies are still making toner for them and I believe you can more or less still get spares of all the other consumable supplies, like rollers and stuff. When I was looking, a cartridge for the LJ4M or LWP600-LWP630-LW16/600PS was being sold by Xerox and advertised as having around 15,000 pages of print life.
With regard to Apple LaserWriters specifically, the only model that I would say to avoid unless you get one that includes a lot of supplies is the LaserWriter Select series. These use a print engine that as far as I know is unique to that printer.
The smaller laserwriters, Personal 300/320 and 4/600 and the bigger 600-16 series share engines with HP printers and so they're easier to find parts for. (I don't know this detail about the LW8500, the 12/640, or any of the color lasers, though.)
One other note about color lasers is that you might not want to go too old if you can avoid it. Really old color lasers like the Apple color laserwriters and the HP 4500/4550 were GARGANTUAN and took inordinate amounts of electricity and had specialty supplies like oils. I don't know if supplies for those are still in common circulation the way they are for older heavy duty monochrome lasers.
Whether you want something relatively modern or modern-usable or want to "collect" something that's vintage is sort of up to you. There's low hanging fruit out there in terms of compatibility. Conversely to the modern laser situation, some of the higher end LaserWriters can accept print jobs over TCP/IP and might be more usable on modern computers as well.
I pretty much outright wouldn't consider buying an older inkjet or dot-matrix printer. Even ones that share parts and supplies with other printers and where you might still be able to buy ink, or use refill kits. Text will look awful by modern standards, probably on either of these, and inkjets were really terrible technology that existed only for cheap, infrequent usage by consumers where $700 + for a laser printer wasn't reasonable. Today, you can get new HP LaserJet for $110, so unless inkjet has changed a lot in the last fifteen years (and: it might have, I don't keep up) a laser printer would be a better buy. (Though on hp.com at least the least expensive handful of models are out of stock, suggesting a possible rush on printers suitable for home as part of the global pandemic, I don't know if this has done anything to pricing on userd printers.)
(That's me though and I have little enough space at the moment that it wouldn't make sense for me to use any printers not usable by most or all of my computers, and, I also don't really have a daily need to print, if I did, I'd get my old Phaser 6120 out of its box.)