You just need to have access to those resources, you don't have to have them within ANY city radius, just within your cultural boundaries, improved, with a road or railroad to them. Or have a very nice civ trade them to you.
The HE + WP combination makes sense. You will probably find that HE, in a good production city, enables you to produce military units very quickly, and you probably won't find much of a benefit from Ironworks.
Furthermore, the HE city should, ideally, be producing nothing but military units. Your IW city becomes, by far, your best production city. So guess what you'll want to build there?
WONDERS!!!
So for several turns, your best military unit-producing city is NOT producing military units. This makes no sense. Put West Point with Heroic Epic and put IW elsewhere.
Ironworks comes along late in the game, and I've recently had my eyes opened to the benefit of putting it in a counter-intuitive location: a city with lots of river and grassland tiles for watermills and workshops.
Usually those are commerce cities or GP farms. But once you have Steel, you already have Guilds (+1 hammer per workshop) and you're not far from Electricity (+2 gold per watermill) and Communism for the State Property civic (+1 food from workshop, watermill). Throw in a really good production resource and you can have an amazing production city, even if you have to replace a lot of mature cottages to do it.
Side benefit: if the city itself is on a river, you can easily build the Three Gorges Dam there.
As for other national wonders with good synergy: If you want to use your IW city for military production, of course you can; you may want to build the Red Cross in this city for units with an automatic Medic I promotion. Or, if this city is a holy city with a shrine, build Wall Street there. If you want to try to produce as many Great Engineers as possible for late game wonders, you could build the National Epic here, usually long before IW is available, and convert its farms to workshops and watermills when the time comes, then run all those Engineer specialist IW grants you.