Here is one that gives 5” of extension.
https://www.amazon.com/Slots-Profile-Picatinny-Bridge-BM1210EX/dp/B00BG22T5A/ref=pd_bxgy_200_3/138-9514786-6362852?_encoding=UTF8&pd_rd_i=B00BG22T5A&pd_rd_r=84e63e92-394a-4012-9e81-a018eb3bbddf&pd_rd_w=ycDOK&pd_rd_wg=NIMga&pf_rd_p=09627863-9889-4290-b90a-5e9f86682449&pf_rd_r=64TAJCZBP8GKP6P6CHYG&psc=1&refRID=64TAJCZBP8GKP6P6CHYG