They look original to me. That's not a common wrap but one that Slingerland did offer. Probably late 70's since the smaller tom is "power" sized. Not sure on the value as Slingerlands tend to be undervalued in general (although they are every bit as good as anything else that was made at the time). The floor tom leg bracket I can see looks to be an aftermarket fitting so probably added later on, maybe converting a large mounted tom into a floor tom (what is the depth of that drum?). That wrap might make these desirable to the right person looking for drums to add to a set in that finish. I'm sure they will sound great in your studio.

Hi, thank you so much - good to know they are genuine; they do sound great so I may just keep them - possibly re-skin them though!

Sam

I'll check the floor tom depth, just need to find a measuring tape!

Cheers

Sam

Agree with K.O. Hard to see in pictures but serial looks to be 48xxxx which would make these early 80's. Probably "Magnums" which may explain the large leg brackets on the floor tom. You can check for similar drums in ebay "sold listings" for an idea on value.