They are exactly like the ones shown, but it's going to take some rummaging to find them so come back to me if your other source doesn't pan out and I'll dig them out to measure. There were off an 18inch frame exactly like the one pictured IIRC.
Conditionwise they should be in fairly good shape as they spent much of their working life wrapped in tape, but there will be marks on the non-taped bits.
Costwise, I'll let you have them for free providing you can organise a courier. I'm happy to pack them up for pick up.