I was helping a guy out tuning his car and found 3 out of 4 booster loose. It's an old school Holley 830 with very little use so I'd like to reuse the other parts.

If I remember correctly an 830 is a 750 base with an 850 main body?

I do not believetThere's aftermarket main bodies to fit the 830. I ran one for years and looked everywhere I could think of. The ones I've found that match the throttle bore are smaller in the Venturi. I believe your best option may be to buy another carb and piece it together.

They make a tool to tighten those boosters up. Its used when we changed to different boosters

I don't believe you can retighten them if they got loose after being installed. I think it requires installing new boosters to get the proper fit. That tool isn't cheap either.

I'd just buy a replacement hp 750 body from Holley or Proform and see how it works.

What is that in the arrow anyway??

You actually can tighten the boosters a bit with the booster install tool, provided they're not too loose.
If it was a race car running race fuel, you could also JB weld where the booster comes into the Venturi........ But it just gets soft with long term exposure to ethanol.

Another even lower buck option for main body replacement is to see if you can buy a used stock Holley main body from someone who swapped theirs out for a Proform unit.
Cut the choke tower off, blend it in........ Should work okay.

You could also send to a carb shop to have the boosters replaced.

Oh....... And I don't consider that an "old school" 830. That's a HP830.

The old school ones had choke towers on them...... Like number 0-9380.
There was a downleg version too...... Can't recall the number though.

Old school to me is non-billet base, bowls and metering blocks. No sight glass either. Manufactured before I had a DL lol.

I used a small punch to re-stake the boosters last night just for the heck of it. I'll run it on my 408 today and see how it acts. If anything it will end up being a parts carb.

Just last week I installed a proform 750 Annular body he got off ebay for $155 & it ran great and made good power. I noticed down low it drove very nice. The swap out is very easy to do also

Cool, I will suggest that as an option. Hoping to get it installed on my truck tomorrow so see how it runs.