Have 2-Gibbs Ascenders for sale. Both in very good condition. One of them has been used as a shunt, so it's set-up with a biner and a pull-down cord attached to it, for safety on your chest sling.
The second Gibbs is of the same vintage and rated at a 1000 pounds, also. Both for $28 plus postage, which would depend upon your zone, but they weigh in at a little over a pound with the biner and webbing. If you don't want the biner/webbing, then it'll be a hair less.
Pictures available.