Good used Super T-10s should sell for about the same price as a good used Muncie. The S T-10 was used mid-70s and later. The regular T-10s were used in the 50-60s and will not stand up to torque of modern V-8s.
To the best of my knowledge, GM never made what I would consider a "good" 5sp. The ones that were available were never intended for service behind killer V-8s. Even the latest, strongest 6sp made by GM was only installed behind a SB. If you don't intend to do serious, hard core, regular drag racing, then a well built Muncie or Super T-10 will make an excellent tranny. Keep in mind that Muncies were used with the baddest engines Chevy ever made. And the Super T-10 is just as good or stronger.
For a 5sp that is essentially a bolt in swap for a Muncie, consider a Richmond. Summit sells them for a good price, free shipping and no tax. Hurst makes a good shifter for the Richmond.
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Tom Parsons