Recently sold off a Gen 4 Glock 21, and took all the upgrade parts off prior to selling. Everything shown here was bought new for that gun, and the round count when I sold it was under 200. Will accept Paypal if sent as "sending $ to a friend" and with Z E R O comments. Otherwise, USPS money orders. See my feedback at ar15.com (same screen name, same avatar, 489 / 100% rating over 10+ years) if you have any concerns.

Overwatch Precision Falx complete drop-in trigger kit with NP3 connector and red safety
$169 + tax and shipping new
$130 shipped here (SOLD)

Zev Lightweight / Skeletonized striker and striker safety (I will include a 2lb and 3lb striker spring and the Ghost Maritime striker spring cups shown
$80 (striker) + $25 (safety) + $12 (Ghost cups) new
$65 shipped for all 5 parts

CruxOrd Aluminum Extended Mag Release (these are really nice if you carry)
$26 + tax + shipping new
$20 shipped with either item above

Slide release and slide lock shown are Vickers and Jentra - not available by themselves but will sell / ship them both for $10 with any item above

See last post for updated pricing*