Magnum Engines OOB?

No it's not. You can buy ASP engines (exact same engine) from Hobby City Hong Kong. Check out their current prices, the exchange rate is very favourable for many countries at the moment.

I can buy a 180 four stroke for less than I paid for my last 91 four stroke. Unfortunately, I already have more new engines in boxes than I have aircraft to fit them to..... ;-)

No. Hobby People / Global Hobby is the US distributor for the Magnum line and they are in stock.

They are marketed under the ASP name in Europe and Asia and Australia. Marketed as Magnum in the USA.

I don't believe the brand name is market specific as Australia has had a rotating series of names for the same engine: Magnum, ASP, and a long time ago SY.