I always thought all d-series non-vtec engines share the same intake manifold and 4-1 exhaust headers with similar port c/c spacing. (Only displacement or more so for SOHC or DOHC configs affects the above) JDM or even USM engineering economises, standardise all parts to simplify logistics, lower production costs and machine/space inventory. The only thing that would be different would be the ecu. Your d15b8 is high on fuel economy. The fuel timing curve would be different from the 16-valve d15b7 you would aspire to have. Therefore I need to know what type of ecu you are using.
BTW I live in Asia about 13-time hours from the west coast, even if I were to sell you my wares the shipping costs is at least same if not more than the item cost itself. Buying from ebay you can at least acquire some legal buyer protection and at least obtain goods of merchantable quality. Its may also better to buy from the guys here, provided they live in or near your neighbourhood and can approach them personally for help if there are any problems with the item or setup. There are also several things to check for when buying engine heads. The camshaft/gear, valves, valve springs/guides, tippets etc.
If these are okay, you will probably need d-series intake/exhaust gaskets which are cheap, new head gasket and valve cover gasket, I would recommend the spark plug chambers 4 o-ring gaskets be changed at the same time to prevent oil leakage.