Raised rivets on Revel's Merlin 101 - how do you get them back if sanded some out.

Archer Fine Transfers has 3D Surface Detail decals that include rivets in various sizes.  They are made out of resin on decal paper and work very well. 

You can check them out here:  www.archertransfers.com/SurfaceDetailsMain.html 

Really, I looked at a number of photos of the aircraft. Those are tiny little things in double rows.

I don't think glue will work. Check out Gino's link.

Dang though at 1/72 tiny.

EDIT: I read your OP more closely- you have most but not all of the rivets.

That makes it nearly impossible. Not to be a d*ck but if you want rivets you might just buy another one. And finish this one with them all sanded off. Maybe with those resin rivets too.

When I mean I have most of them, I mean that in a line of rivets maybe half of the rivets in that line has been sanded down where I needed to close the joint.

In a full line, perhaps the Archer things will work...

In 1/72 if you sanded the remainder off and used a roller to "add them back" the eye likely wouldn't be able to tell they are indented vice sticking out under paint and a wash.  If you have an old model or some scrap plastic give it a shot.  If you don't have a roller-style riveter, you can use a pin vise and a needle to see how it looks, but I would recommend using a roller on your model for alignment and spacing.  Dymo tape (sold at office supply stores) works great as a guide for the riveting rollers.

If you opted for the archer transfers, I imagine they would be ever so slightly larger or smaller than the ones molded on the kit and you might need to replace the ones you saved anyway.

Groot

A hacksaw blade also works well as a guide for getting a straight line and even spacing if you want to indent them using a needle.

The better rivet-rollers are shaped to more closely resemble the 'dimple', in that the point indents, creating a donut of raised plastic round the dent.

The skill lies in getting them even, & correctly spaced. Dymo tape, double-thickness Tamiya tape, PE templates will help. good luck

when I lost some on my fw-190 I used the archer rivets to bring them back, easy to use and turned out great