forming 350 Rem mag brass

Well I have a little bit of a problem as of late. I have 28 pieces of very tired 350 Rem mag brass and what little brass Remington does make for this caliber goes to their dismal factory loading that wont shoot minute of barn in my rifle. My hand loads have been around 1.5 moa which is adequate for what I do with this rifle. It is not for long range, but for carrying and thick brush/timber. The brass That I do have is showing signs of impending case head separation and neck splits are getting common. I need to start making brass out of 300 Win mag, 7mm Rem mag, or even 375H&H if I can find it cheap and it is decent brass. My questions are, where can I get the dies to form the brass I need? What else will be necessary to form this brass? What brass would you start with? I am not an idiot but I have never had to form a case from a different case and my experience with reloading is fairly basic testing of bullets, powder/charge weight, resizing cases, not blowing my hands and face apart, the usual stuff. Your help is very much appreciated as there really isn't much time till Elk season, and I need to re-develop loads, re-sight in and practice after I have some brass.
There's a YouTube video showing how to form 7mm Rem Mag brass to 350 Rem Mag at:



But in searching for a way to form 30-30 Win brass down to 25-35 Win I came across Redding's list of popular reforming/trimming dies and I noticed that they listed the solution to your problem in a single 338 Win Mag to 350 Rem Mag die for only $66.50. Unfortunately for me the 25-35 solution requires 2 dies for nearly $200! But you can find that Redding list at:

 
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