You rarely will find them sold at MSRP. Frequently they are double MSRP. Assume $8.00 MSRP, actual store retail price $14.00 + tobacco tax(37.5%) and state sales tax(7.5%) = $20.00 a stick in some states.
If you have a long term relationship with a local tobacconist, where you have done considerable business, you may get a few each year at MSRP. The Fuentes deliberately control distribution so the prices remain very high.
The only way you'll be able to trade for Opus X using an $8.00 trade value, is if someone is giving you a gift.