you can get a used rear for like $400 and swapping them out is about as hard as putting in lowering springs
shit people on my local site sell complete 8.8 w/o brakes for around 150. Buddy of mine is selling one with newer 373s and brakes with drilled rotors for 150.
your parents must be like mine. when i was home i would have to ship stuff to a friends house and put it on there. my mom dont care if my dad spends thousands on their harleys or his street rods. he actually bought more stuff today for his 32 coupe. God forbid if i buy a short throw shifter, or gears.