Halo B used to be the standard. Empire makes fast loaders too. I would honestly looked for a newly used hopper on Craigslist or Spec Ops. I know you can find one for less than $115.00 for sure. Heck, I bought my gun off of Spec OPs and it's been my pride and joy on the field for over a year.
I am going your advice and Getting a Dye Rotor