Any reason why I can't seem to find any difference (other than the discontinued manufacturer number) between this sight rail a guy is selling on gunbroker:
and the one that HK Parts has for $50 cheaper:
hkparts.net
and the one that HK Parts has for $50 cheaper:

H&K G36/SL8 (5.56/.223) Sight Rail With Front & Rear Sights
Get your New H&K Heckler & Koch H&K G36/SL8 (5.56/.223) Sight Rail With Front & Rear Sights for $289.95 at HK PARTS today! - HKP-00274
