Rem700 Mcmillan stock how to extend 3/8"?

[yocan]

I have a rem700 done up by Weber customs, the combination of optic/gun/orangutan arms I need to get a 3/8" to get a full sight picture.

It has an decelerator pad on it (~4.5" on the buttstock 5" pad) I don't know which Mcmillan stock it is. So hoping someone on here knows enough from the 2 pics to go "get this" or at least tell me what to look up.

 

[Maxduty]

RIFLE STOCK SPACER | Brownells

Fashioned from durable black polymer, these spacers sand and polish to a high quality finish. Slotted mounting holes make it easy to match most screw locations for ease of fitting. Three spacer sizes allow custom tailoring for length of pull. Adds...

www.brownells.com

 

[camocorvette]

Kick Eez Stock Spacer 1/2 Black

These spacers are made from a strong lightweight plastic polymer that are easy to fit, grind and finish. The extra long slotted hole at the toe of the...

www.midwayusa.com