Cheers:
Don't as know much about Herse as I do other French constructeurs. I thought the lugs were not typical Herse, then I found this at Alexandar March's site:
Exceptionnel vélo Rene Herse diagonale. Wonderful Rene Herse.
which has the same lugs. There are some really expert Hersophiles over at Classic Rendezvous with a lot of insight and knowledge who can give you info, but won't give you a valuation 'cause it's against the rules. Some of them also frequent here. FWIW, Herse's with a Herse stem and cranks are much more sought after.
Ray H.
Sudbury, Ontario
Canada