Some update on this subject;
So I purchased the black bumper to give it a shot. It was pretty sloppy in the hole, and I didn't really think it should be that loose, so I ordered a red bumper as well. The stem was a bit short and the rubber seemed very soft - so much so that the little "tabs" on the stem would not hold it firmly in place. But with the clutch pedal up, it was held there just fine ;-)
Was reconnecting the brake booster a week or so later and took a look at the red clutch bumper. Hmm... I think I have a match, LOL!
Some pics:
Comparison pic of both bumper versions, as well as the remains of my original.
Original red bumper remains when they were still in place (2pics)
New bumper after a week or so installed.