I use an old sabine RT-1601. it tracks a little slow but it's accurate and seems to pick up the lower string better than the DTR 1000 I used to have. As for who is currently making them the only companies that come to mind are Peterson and Behringer.
I think it would be worth it if you could find a Korg DTR-2000 used somewhere. I didn't know they weren't making them anymore, but it's definitely a solid tuner with lots of routing options.
The DTR-1000 is a great tuner and simple. I like that it also has an extra input so your bassist or someone can plug in and tune without messing up your rack.
Sidenote - I have a KORG DTR-1000 available in the market, only reason I would get rid of it is because my AxeFX has an onboard tuner. PM if you're interested.
Didn't the whole rack tuner market get shut down because of something to do with weapons manufacturing? I could swear I read that on here, but I have been playing a lot of video games lately...
Either way, my rack has a slide-out shelf for pedals, so I just keep my boss TU-2 on there, along with my X2 wireless and other non-rack mount stuff. It probably saved me about 4 or 5 spaces in the end actually