I haven’t found much once fired brass. Star line has new for $99 for 250. PSA has the federal on sale sometimes, box of 20 with shipping and tax is 9.99
Look on the 6.8 SPC forum. I see 6.8 brass going for 30 to 45 cents each based on brand, primer size, etc. The challenge will be the amount of shipping for only 60 rounds brass.