Look up Myastro shop. Steve has a black ST80 for $150-$160, much cheaper than Bintel's Orion white one but the same scope. Use a 24mm 68º eyepiece...RFT heaven, even better a 2" focuser with an ES 34mm 68º.
I like scopes to look good
as well as perform, so I'd choose a white one to match the rest of the scope!!
Are the 90mm rings guidscope ones...that is with the 3 adjusting screws on each ring?
The Orion rings are cheap and good. I use them on my 90mm f11.1 refractor no problems.