Cost of narrowing axle

i've been debating on running an irs in my truck and i've found out prices are about 300-500 to have an rx7 rear narrowed and convert the driveshaft... if i don't go with an irs, i'm going to be narrowing a toyota axle.. can anyone tell me what they've been charged for narrowing a straight axle, or an independent so i can get a better idea of the costs for each. Thanks

I went to Mosier Eng. in Fort wayne IN, They made new axles, and narrowed the housing for about 300 all together. Its a two day turn around. You can drop it off monday and pick it up on Wed. Mines held up 4 years+ without any problems!