Tires!

[emptysea]

My decision <drum-roll> :

I'm going to attempt to plug the tire from the outside using the Stop & Go mushroom-type plug. Assuming that I can get the plug to fit correctly, I will monitor the air pressure even more carefully than I already do. If it holds, I will ride with it until such a time that I feel that I should replace both front and rear tires (ideally around the end of August).

If the plug fails, then I'll probably go for Option #4 - Relatively cheap tire for the rear until the front wears enough to replace both with new PR3s.

Thanks for all your input. I'll let you know how the plug works/doesn't work.