I would pay big bucks, and I'm sure every one here would too. 1 -10 round LAR-15 magazine: $40. X3 for 30 rounds: $120.
Hell if you charged $100, everyone would still be getting a deal. Nevermind the fun factor and the obvious benefit to matches.
And to who ever was talking about a modification to the mag so it won't fit ar's.. you've got it all wrong. You point out to me where that is stated in rulings/law. It has been stated that the legality of a magazine depends solely on what it was designed for.
10 round pistol mag that is designed for the pistol, but just so happens to fits in rifle = ok (LAR-15, Storm, AR glock mag conversion, etc)
10 round bolt action mag that is designed for the rifle, but just so happens to fit in rifle (AIA enflield with magazines that fit into M14's)
10 round pistol magazone designed for one caliber, but fits and functions with another = ok (Sig P226 in 40 with a 9mm barrel can fit 13+ 9mm rounds into the 40 mag, and is legal because the mag was deisgned for use with 40 cal ammo.)
That being said. If someone makes a bolt action rifle, with proprietary magazines that are designed for use in such, and just so happen to fit AR-15's than that = ok. the reason the remington pump rifle mag was not approved was because it was advertized that the magazine for it was already designed as an AR-15 magazine. (Or the mag well, I forget)