I'm assuming you have a worn gun, so will answer several questions which you didn't ask, because there are many thousands of very delightful old guns which are considered wall hangers, though LBT has the technology to help you make excellent shooters out of them. There is an itch that gets scratch when shooting grandads old rifle, or some nostalgic military piece that cannot be itched with newer guns. My catalog says I no longer make custom molds, but that does not apply to custom diameters. I will cut any profile listed in the LBT Catalog to any diameter needed to fit any gun from 22 up to 512 diameters. Many can be fitted for gas checks though non are available for the caliber, by providing a check shank to fit the next larger size available.
The shallow rifling is not a problem at all. If the throat is long, choose a heavier weight, if short, the lighter weight, so chambering isn't a problem. Or go with the 200 gr if you want to keep recoil down. The LBT Spitzer form is very stable in flight, hence easily stabilized with moderate velocity, or can be driven at high speed as desired.
Understand that the real problem which encountered with shallow rifling in most cases is that the gun is worn oversize. When standard diameter bullets are used in the oversized gun, with the throat being the most severely eroded area, the bullets tip a bit when getting started. If a bullet tips at all on takeoff, no rifled firearm can straighten it up in the bore, be it fixed chamber or revolver. Shooters without means to pinpoint the real problem therefore blame the problem on shallow or worn rifling.
I once made a mold for a gun so worn that the rifling was invisable on a swaged bore slug for the first 10 inches of bore, but .001 of variation in diameter could be measured with a micrometer. By fitting that 303 Brittish double rifle with an oversize bullet to fit the throat just ahead of the cartridge, the rifle which seemed to be worn out, shot both barrels into 1 1/2 inches with full power loads.
As a general rule, with cast bullets fitted to the individual gun, worn barrels will outshoot new with cast. Don't make the mistake of thinking a bell mouth muzzle will shoot accurately if diameter right at the muzzle is larger than the bore. I have obtained excellent results with a few of these by lapping until the grooves begin to shine or "clean up", to use machinest terminology. Even though the rifling may be worn almost entirely away, accuacy will be excellent if the grooves maintain a grip on the bullet as it exits the muzzle.
Cloudy bores are actually fine rust pits, where the rust rises above the original surface, in effect reducing diameter slightly. Lapping with the LBT lap Kit will fix these.