https://retro-access.com/ is a US seller of the highest quality cables. They are a bit challenging to order from, however. You have to get on their site at 10 a.m. EST, as that’s when they make everything available that they have parts to build. Great products, though. Half of my cables are from them.
The other half of my cables are from retrogamingcables.co.uk. Their prices and quality are comparable, and they offer free shipping to the US and Canada. It can take a few days longer for your package to arrive due to coming from overseas, but that’s the worst case scenario in my experience…a few days. Their website is easier to order from.
Anybody have any other recommendations, stateside?