Welcome to our forum.
so open seat design? hmmm...here I'll assemble a "shopping list" for you Hot Spring VanguardLimelight PulseJacuzzi J-365Sundance Optimamost of those are only a few inches smaller than what you currently have but are all excellent spas imho
I looked in Craigslist-Columbus area to see if there were any free spas for the taking or anyone selling new ones out of a storage unit but I didn't see anything enticing.Get yourself a nice 7' square non-lounge spa from whichever dealer in town carries a great product and who you think will be around for you. Good luck Bill, I think you know the routine on how to go about this.
Don't be tempted by the dark side. Get a premium made spa, they stand the test of time.