>>630600I don't bowfish, but I've looked into it before.
The cheapest would be a homemade reel screwed into the stabiliser hole on your bow. There're a few youtube videos on how to make one. You need to spool your line back on by hand though and it looks like there'd be more potential for it to snag and fuck up compared to a bottle reel like in your picture.
Obviously you'll need a fibreglass fishing arrow and a bow fishing point. I feel like the safety slide is a good thing to have on there re: avoiding getting line in your arrow rest.
Are you going to shoot fingers or with a release? If fingers, you might need to think about spine on your fishing arrow. I've got a long axle-to-axle compound amongst my stuff and my normal arrows are way over-spined if I finger shoot it, hitting about a foot right even under 10 yards.
In terms of a rest, I reckon a whisker biscuit would do a good job and it's probably the cheap option compared to some of the specialised bow fishing rests around. Easy prep and secure, full arrow containment are big pluses.