Be patient. I told my partners when you own your own business, you only have to work 1/2 a day. Just pick what 12 hours you want to work. Just dont try to grow to fast, take your time.
So if you send someone a package 2 day priority with conformation and it takes the post office 4 days, is it your fault? I don't think so. You can't blame the business for USPS shortcomings. Once it leaves their facility, they have no control over shipping.
Also check yor state tax code for inventory tax. Raw material is a tax deduction but once you make a lure, it's a salable product and inventory tax would be due.
Bass tackle injectors are the easiest to use with the quick disconnect nozzles. Baitjunkies plastisol is the overall value pick. I would check the classifieds and Ebay for injection molds. You can pick up some good deals there.
You can try a local boat repair shop also. Most may trade some for a few bags of baits. You can also get some unique colors and they tend to have larger sizes than regular body shops.
Check with your plastisol supplier and ask them to sell you some MSO. MSO is essentially worm oil only cheaper because it's not called worm oil. ( and no scent or glitter.)