The Bear tooth bullet is 60gr. It will probably not give adequate accuracy in Hornet for shooting squirrels.
There's a lot of derision written in rimfire.com about the Aguila 60gr load and it's poor accuracy.
I was even afraid that the 50gr Lyman bullet would not be good, but from the 1-14"twist barrels of the Rugers it shoots ok.
If you don't want to cast (You probably could set up and cast a thousand for what it would cost to buy 500), I would just buy some Remington 45gr soft pt. bullets from Wideners or Midway, and load with Unique to the velocity you want.
The 4.0gr load mentioned above would be about right.
The amount of damage done by a 45gr. jacketed load would probably be no more than the cast, and less than a .22rf-mag.. I've shot some squirrels with a 45gr Hornady Hornet's at full velocity (head shots) and still was able to put the squirrel in the pot.
Another good choice would be the 50gr Hi-vel. Sierra bullet which is jacketed and alloyed to shoot through .22-250's and .220 Swifts. It would expand little, and would be quite accurate.
Try the Bear-tooths though, you may have to work up your own data though as I've never see data for a Hornet w/60gr bullets.
A set of Lyman or RCBS moulds with Handles will run about $65.00. A Lee sizer is about $13.00 , and a 1,000 gas checks will run about $15.00. For shooting squirrels with 3.0 Bullseye, you could tumble lube the bullets and get acceptable accuracy to 40yds or so.
Good Luck !