Sure thing Tony, these are Dunlop Herco thumb picks. They come in different colors/thicknesses. These yellow ones I have are "light". I see some yellow ones online that are medium. So... watch what you order as apparently color does NOT indicate thickness. I will tell you that the part that goes around the thumb is a very light hold compared to other thumb picks, so I'd be concerned about a heavier one staying on the thumb well during upstrokes (although, if you're going to hold onto it like a normal pick while it's attached to your thumb you should be alright).
I have no clue if this site is any good or not, but I happened across stringsdirect.com and it looks like you can buy them one at a time in the UK from them. Most of the sites that popped up in a search were a box of 4 to 24.
I LOVE those Dorito picks! My hubby laughed at me when he saw I had bought more of them! He hasn't heard my string muting yet however, when he does and sees I'm holding that big ole Dorito to get the job done he won't be laughing any more!
I saw the "News Flash" ... sadly I won't be getting out of dish duty until my two girls are old enough to wash dishes. Being the only female in the house tall enough to reach the sink without a chair I guess makes me "chief bottle washer and cook"!
Art and beauty are in the eyes of the beholder.
What constitutes excellent music is in the ears of the listener.