OzFclass

Would $4500-$5000 get me a decent quality f class open rifle?

Rifle, probably. See agro's post yesterday; a high-end setup for around the $5500 mark.

All the gear that goes with it? Not very likely unfortunately. The rifle itself is probably 25% of the equation. Rest, rear bag/plate, higher-end scope, mat, are the basics of on-the-mound gear you'll likely need.

But the bigger chunk is in the reloading equipment; the dies, annealer, case trimmer, presses, cases, projectiles, primers, powders, scales, measuring tools, gun box long enough to suit it, barrel tuners, neck turning gear etc etc etc that all add up to a bunch more than the rifle will cost you.

Can you buy a quality rifle for F-Open for $5000? Yes.
Can a newcomer sign up and compete at the higher end of F-Open for $5000? Honestly, no.