I'll assume that you only need it to hold US currency.
I've used both of these, and would be happy with either. The Levi wallet just needed more 'maintenance' and was heavier. The bill clip needed tightening on occasion. Outside access was easier with the Levi wallet.
http://www.amazon.com/Levis-Front-Po.../dp/B002OB42A2
http://mostrad.co/collections/frontpage