Re: To-be-hubby’s birthday 
You can search on google, areas near you who customize picks. But you need to know the thickness of the picks your husband uses, its important to each guitarist.
Does he play electric or acoustic? If electric ( I know more about these than acoustics) , would you be interested in getting him a brand new guitar?
Processor or Strap? There are so many guitar related things you can get him, which would be meaningful.
Good stores in the U.S.:
Drum City-Guitar Land: Very reliable, on time, and best sales. That’s where I got him the schecter loomis 7-strings (beautiful guitar, after 4 years he still can’t stop thanking me :D)
Musician’s Friend: Again, great prices and on time.
Pickfactory: I believe it’s in Europe, but looks good.
hope it helps!