Yeah the cape is easy to spot by feeling it, thickness and softness. an original YPS cape feels diffirent compared to an regular hoth troopers cape, but also different as an repro cape. To learn to know the difference you should buy an repro cape and compare it.
This is how i startted off, i bought an set off all repro weapons and repro capes and used this as to learn to spot the difference btween repro and original. About the the rifle, this you can tell by looking at it, there is always a difference in plastic between repro and original weapons also the molds can vari.
By the way, there are repro yps guns, but there also alot off original ones since this weapons also could be found in a GI joe action pack. (Like star wars had the hoth pack with backpacks, gasmasks and rifles.)
By the way if you need an YPs rifle search such an sealed Gi joe pack (these are fairly cheap) and you'll get yourself an 100% authentic yps gun.
Cheers, Dennis.