I'll keep my eyes open for the article, but can I ask if you're looking for practical advice from that article?
Bullets for .429 have changed pretty dramatically since Milek's day. It's very likely that he would have used the 240 grain jacketed bullets available then. Today, I'd be looking at some of the newer designs of heavier bullets. I'd probably start researching with good loads for the 265 grainers. Or some of the really nice hard cast bullets, if the rifle in question has rifling that is compatible with them. I don't know if the 444 is micro-groove rifling in their lever actions, but if it is, you probably need jacketed. There may even be some of those soft tipped Hornady lever action bullets available for it.
There have also been a lot of new powders and loads developed in recent years.
Scopes for lever guns are much better too.
If it were me hunting them, I'd make up a bunch of ammo, then get proficient with the trajectory and wind drift out to 300 yards.
I just checked an Hornady does have the Lever bullets available. Note the trajectory. Some tweaking by zeroing somewhere between 200 and 300 yards should make it adequate for hunting out to 300.
http://www.hornady.com/store/444-Marlin-265-gr-FTX-LEVERevolution/