I must say I'm surprised they still hold air!!
What are the rest of the Tubes like?
I'm sure Henshaws could sort you out some Hyperlon cut to size if you have someone to overlay it.
Personally Id Definatly get a pro to do it...AND WHILE it still holds air ok!!
..otherwise I reckon it'll be a re-tube.
As to "thin" Hyperlon,and I'm not sure there is such a thing!
Anyway,Why bother?...the normal grade opposed to the thicker grade/commercial will do fine.
Either way,by the look of the Tubes.. I reckon it'll only be a temporary solution.
How old is the RIB?...IF the rest is OK it may worth thinking about having the lot replaced,it's up to you to decide what is the most viable/economic solution.