I looked into this as I was going to use a mates 44 mag on a trip. Its significantly cheaper, especially if you aren't using full power loads and can take advantage of cost efficient powders like Trailboss.
Check out the Black Widow range of projectiles. They're coated lead and I've had good results so far in my 45-70 using them. They offer 44 mag projectiles like these (
click here) which are 55 bucks a box of 250, plus postage or get them into your local gun shop.
So even at 60 bucks a box thats 24c a round. Add in 5c of primer and, what 10c of powder or so, and you're looking at under 40c a shot excluding your reusable brass. [ EDIT: They also do a 165gn projectile for 62 bucks per box of 400, thats 16c a round. Makes for good cheap plinking if you're so inclined. ]
40c a shot vs the cheapest PPU stuff which is usually about $1.20 a shot... you're well ahead and can tailor the loads as you wish.
Honestly I'd grab a box of PPU, see how you like the feel of those to shoot, and go from there. At least you'll have a box of 50 of them or so to go to the range / paddock with and then some brass to work with after that. I only recommend this as you can run the numbers, find out the foot-pounds, and then work around that when you pick up the reloading book.