I am a current team tournament angler and I am thinking about moving up to the coasta's or the opens in the next year or two,

My question is does anyone fish these higher level tournaments out of anything other than a traditional bass boat?

I currently fish team tournaments out of my 19' stingray fish&ski combo with a 225hp I/o, so its fully tournament ready.

I just don't know if it would be acceptable and if so if I would be the only one not in a brand new nitro, ranger, skeeter, ect...

as long as it floats, and meets the rules and law. Fish it. I have had my arse handed to me by guys in Jon boats and 9.9 kickers more times than I'd like to admit.

Should be fine. Just check the rules. 

Many years ago , I fished RedMans and then BFLs when the primary sponsor was Walmart; this is the same tournament trail as the current  Costa. I've been in 21 foot Rangers, 20 ft Tritons, 19 ft vintage Rangers, 18ft Lowe Mod Vs, Bass Trackers and I've also seen boaters competing from fish n ski boats at various levels of competition. Not everyone is going to be fishing from $80,000 dedicated fiberglass bass boats, so I wouldn't hesitate to compete; as long as you meet the boat length requirement, motor requirements, have a kill switch, life vest and functional divided live well ....then I think you are set .