I mean, you can retrieve your cameras back so in total you need just 21 cameras. which is 21k$ and to be fair that's not a grind. Just play the black jack or horse runs (split your money if you do that one) and gamble it all after saving. If you lose load the saved game and try again.
It's just gonna take you about 11 attempts in blackjack to get 50k$ and that's assuming you don't know how to play blackjack and your luck is awful.