I've had a very similar experience.
I bought a Promaster used about a year ago, and the cupseal recently went on it. So I ended up messaging them on IG and got a message from Gary a few minutes later to shoot him an email. He asked if I needed the whole brass cup for $4.95 USD or just the seal for $1.50 USD. It ended up I only needed the actual seal, and was asked if I'd like it to be shipped with a tracking number or just sent in the mail. So I obviously picked the mail, and it was sent to me free of charge (to Canada). It may have just been cheaper in PayPal fees and paperwork to do this, but it was a very nice gesture, and doing it bought them a customer for life. So it shows up about a week and a half later, and there is not only 1, but 2 seals. Those guys rock.
All in all the experience was excellent. Not only did I get what I needed for free, but I got it fairly quickly. My emails were responded to almost instantly and Gary left me with no questions.
I've been meaning to make a thread on this, but since you've made one already I'll just piggyback off yours.
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