This Shops offer SDIY/electronic music kits (for part reseller check out this page)
http://www.thonk.co.uk Euro/4u
http://www.munichen-audio.de Euro
http://www.frequencycentral.co.uk/ Euro
http://www.oakleysound.com MOTM/MU/Euro
http://synthcube.com/cart all formats
http://www.cgs.synth.com – ken stone
http://electricmusicstore.com/collections/all Buchla Pcbs
Standalone Effects
https://pcbgrinder.com/index.php?route=common/home > GSSL compressor and other Studio gear like 500er series
https://www.don-audio.com/Startseite > High Effects Parts for compressors, VCA and more