Where can I get quality, or better yet, the finest made stripper decks? Some of the ones on the market are very poorly made and the taper is visible whereby you can obviously see the narrowing white border. I need a professional grade source.

I am looking for Bicycle Rider Backs.

Thank you.

Try searching for hand cut stripper decks:
https://www.handcut-stripperdecks.co.uk/

There is a banner ad in this very section for the Deck Tailor. He does exactly what you are asking as well as paying for an ad to support this forum.

https://www.donboyermagic.com/

Hi Poof, that looks like it will be perfect. Hand made.

Thanks folks.

I would check with Marty "Martini" Grams. He will make you whatever kind of stripper deck you want. He can set his cutters to "your" specifications and his prices are reasonable. He knows a lot about stripped cards. Worth giving him a call.
http://www.martinismagic.com/