Harbor Freight has a parts warehouse, I THINK it is in California. They have a toll free telephone number so you can call them and order the part you need. I had the phone number for them, but I don't recall where I wrote it down. I have ordered parts from them in the past, got thru right away and they had very good customer service. Additionally, they were very good about getting the stuff I ordered shipped out right away.
If you call a Harbor Freight store near you, or just go and talk to someone in a local store, I am sure they can give you the telephone number to call. Give them a call, have the model number of the item that you need a part for, and if you have a part number that would be even better. I didn't have part numbers, just a model number, but they looked up the part numbers while I was on the phone with them, they gave me a price, it was less expensive than I had figured, and I ordered the stuff with a credit card. I was very happy with the way it worked out.