I have shot a lot of Montana Gold. I think you will find 4.3 gr of Win 231 OK. I like Unique for the 9MM as well. some say it is a dirty powder but I clean my guns after every session anyway so really consider this a non-issue for me.
Here is teh name of a company out of Quebec. I have used their bullets with great results - industriecampro.com. Bullets might be cheaper than Montana Gold.
If you do try Unique 4.7 gr under 124 gr bullet is a good accurate load in my guns. You didn't say what gun you are shooting.
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