I've chased gold in the vein with a detector that I used to have. It worked for doing that, but I can't say it was my favorite detector.
I used to have a Garret Scorpion Gold Stinger. The gold circuit on it worked fine, after I found out the manual had a misprint telling me to turn the ground-balance knob in the wrong direction!
Regardless, I figured it out and it worked fine. I also found nuggets with it. And, by the way, it had a coin circuit with discrimination as well, so you could hunt coins with it.
I would imagine you could pick up a used one of them for under $300.
If you've never chased gold with a detector before, you need to make sure you know how to ground balance properly, know how to ID hotrocks and mineralization, etc. It's not like hunting for coins, and it takes a while.
Find some good Youtube videos to watch, read my main thread for some tips
http://www.treasurenet.com/forums/metal-detecting-gold/69-bedrock-gold-mysteries.html or skip over to the Gold Prospecting site and search through it for tips. There's some good links for learning how to hunt with a VLF on the Net:
http://www.tekneticst2.com/tekfiles/Dave'sGoldbook-printer.pdf and
Teknetics Tek Files
Here's another link to one of my pages that others have added to as well:
http://www.treasurenet.com/forums/gold-prospecting/398442-gold-hunting-prospecting-tips.html
All the best as you learn what to look for in a VLF machine within your budget range,
Lanny