I have done a couple of dozen custum rifles over the years. some with custom actions, some with Remington actions. For a 358 I would not use anything but a Remington theres no benifit with a custom in that caliber except you can say you have one. Barrles, and stocks are a diff. matter. MacMillan, and a Hart, or Lilja barrel goes on all my customs. the last custom hunting gun I did was a 250 sav, and 22/250 swtich barrel. I used matching Hart barrels in a #1 contour. With a MacMillan model 7 stock, trued Remington action, with a factory trigger set at 2-1/2 pounds. I had the action. The barrel and work was $600 per barrel. The stock, and work was $650. The action trueing was included in the barrel work. This is not a varmint rifle but a deer, and coyote rifle that wieghs 6-1/2 pounds witha burris compact 3x9. The 22/250 does about 3/8 for five shots. The 250 sav. does about 3/4 with 100 gr. Nosler part. and 1/2 inch with 75 grain v maxes.
