In response to a request a few months ago I found in the Histarch archives
here are details of Society for Post-medieval Archaeology (Paul Courtney).
 
Subs payable sterling or US dollars only.
Normal #15 ($30) a year
Joint #18 ($36)
Student <25 #8 ($16)
Retired >65 #8 ($16)
 
Annual journal and twice-yearly newsletters. Also conferences, mostly in UK.
Backnumbers vols 1-29 available, please contact for quote
 
We now have a VISA payment facility
 
Address: Paul Courtney, membership secretary, 20 Lytton Rd. Leicester LE2 1WJ
United Kingdom or Email: [log in to unmask]