I've been doing some experimenting with 180 grain cast bullets in my Marlin .357 carbines and they work really well. They have a long bearing surface and I'm driving them hard. In fact, the energy level is right up there with the 30-30 Winchester with 150 grain bullets. I've cast them from straight linotype and they come out at about 175 grains, where wheel weights from the same mold come out about 185 grains. I've settled on Lyman #2 alloy and that drops them right at 180 grains. All three alloys hold the Micro-Groove rifling just fine. So far, Hodgdon's LIL'GUN is producing the highest velocities and decent accuracy in the Carbine.
In your case, you can't go wrong with Oregon Trail Lazer Cast Bullets. They're about as hard a cast bullet as you're going to find, without casting your own.
As for plated bullets, they really shouldn't be run over about 1,250 fps, or you'll have them strip the rifling and tumble. I'm running Berry's 124 grain plated bullets at 1,300 fps in my 357 Sig Springfield XD and they're very accurate, but at anything over that velocity, they tumble. I haven't tried the Berry's plated bullets in my Carbine, though.
My wife and I shoot several thousand cast bullets per year through our Marlin Carbines for SASS matches and practice, but these are light loads. I'm currently using 128 grain RNFP cast bullets from Berry's Manufacturing. It's a good bullet and feeds very smoothly through the lever action Marlins. I don't publish loads, but I'm using a light load of Bullseye at this time, but when this keg is gone, I'm switching over to Hodgdon's Clays for a cleaner burn and less smoke, though with cast bullets a lot of the smoke is due to the bullet lube. When I run out of the Berry's 128 grain bullets, I'm switching to Bad Man Leather & Bullets 130 grain RNFP, since a four of us went in together and bought 40,000 of them.
Some of the lever guns can be tempermental on what they will feed. Generally, the Marlins like a longer overall length when shooting .38's through them. Each one is different, so you'll have to experiment with your rifle when you get it and see what length feeds the smoothest. Our guns have had action jobs from Pioneer Gun Works, in Springfield, OR. He does a really nice job of smoothing up the action and takes all the jerkiness out of them. Here is the link to his action job page:
http://www.pioneergunworks.com/wst_page7.html
Hope this helps.
Fred