I have ordered the proper replacement o-rings for the Prest-O-Lite. Still waiting for delivery 2 weeks later. In the mean time, I picked up one of the knock-offs, an Acet-O-Lite torch kit by Goss, at a flea market, complete, and in it's origional packaging, for $10US. If the new o-rings don't fix Dad's Prest-O-Lite, I'll use the other.
Chuck