At my LBS, 10-speed Shimano triggers start @ $66, 8 speed @ $40, Gripshift 8sp @ $20.
Unofortunately the Gripshifts are MRX. Glad I got some of the Mid-range Gripshifts when they were still available, still haven't even mounted them
Cassettes and chains are still available and cheaper, also. Buy two cassettes and that'll probably keep you going a good long while. 8sp chains will still be around in 10 years.