[OTHER] Right bow length

Hi all, after getting back into archery I've just found a local club that shoots 3D. Really fancy this but don't want to carry round my target compound. So, I've got a samick discovery field recurve riser and would like the matching limbs. How do I determine if I need the medium or long to make either a 60 inch or 62 inch bow? 17 inch riser. I've asked a couple of shops but they just seem to tout what they have in stock. Not really what I want to hear. Sorry if this is a daft question but just want to make sure I have the right limbs for myself. Thanks.

Brett