Line recomendation

[GermanG]

I recently picked up a mint condition Cortland Rimfly reel for $10 at an antique store. Made in England. No box/manual. An "M" sticker on the reel seat. Means medium, perhaps? The reel is about the size on my old 1494 1/2 Medalist. Anyone familiar with this reel and the line weight range I should be looking at? Want to set the rig up primarily as my spare rod.

 

[lightenup]

It is made for 5 or 6 weight lines. But a Terrenzio faux silk line on there, they are fantastic.