Need advice on where to buy and how to install a larger loop lever on my 10-15 yr old marlin 3030. Is it something I can do myself or do I need a smith to do it?
Also, where should I buy from and what’s a reasonable price?
Any and all advice welcomed. Thank you. Just need a bigger loop on my lever action for my big paws.

I did mine myself.
The problem you might have is finding the Marlin big loop lever. They are scarce right now.
There are some aftermarket options, but I like the Marlin lever better and the price was better than the AM's.
Make sure you choose the correct part....for pistol grip or straight stock.

Ranger Point Precision
Wild West Guns
Jard
Beartooth Mercantile

It's very easy. One screw and pull the lever out and slide the new one in

I got a ranger point and very easy to install on my 1894

Another vote for Ranger Point Precision. I have one on my 1894 .44 and love it. Its bigger without being obnoxiously so.

I have a Ranger Point Precision on my Guide Gun, and it gets my vote, also.

Ranger Point Precision I have was a disappointment. Looks cheap, Poor finish. Junk drawer.

WWG: little bigger loop. Stainless or blue. Better looking. Smoother operation. Better decision. Almost a duplicate of the Ruger SBL.

Had a WWG big loop on a 45 70 yrs ago......too big for me.......dumped it

Ranger Point gets my vote

My question ?

How have you been cleaning your 30-30 ?

Easiest & best way is to pull lever & bolt (don't lose ejector spring)

Clean from the chamber end not the muzzle

Your replacement lever will take time to to 'wear into' the older action

Buff the sharp edges....while you're at it pull it down & buff the internal moving parts too

https://rangerpointstore.com/marlin-medium-loop-lever-black-nitride-1894-336-444-1895-450m/

http://marauder.homestead.com/files/TUNING_M_1894.htm

Not throwing shade, but have you EVER cleaned it in 15 years?
If you can do one, you can do the other.