Slide wheel or rule glide computer, where to buy?

Can anyone out there tell me where I can purchase a small hand held final glide
computer (like a revolving or slide rule type) that can be easily
used to compute final glide from GPS data (eg distance to fly,
head and tailwind components, altitude needed etc)?

Years ago I had a FSW or FWS glide computer, that I bought from wings and wheels, they no longer have any and I cannot find the one I purchased years ago.

Thanks