Well on number two Jeff has covered, as does Congress. The US DOD will never more then sample a foreign made weapon system. By that I mean one or two prototypes might be imported but after that production runs will be American made. The only exceptions are for none combat training and evaluation.
for example leasing of A foreign SSK to practice sub hunting or evaluation of a former East German Russian made patrol ship. Flying Mig Aggressors or using Russian and European aviation assets to simulate a foe. Or using Russian and foreign made vehicles to equip Opfor. If the US liked at say Horizon class frigates, the US would build them here.
second the US actually has been buying a lot of foreign designs lately, UH72, VH71, Stryker infantry combat vehicle/ LAV25, both Independence and Freedom class, Joint High speed class ships, AT4, M777, C27J, MH67, A29, a number of UAVS, M27(HK416), M32, M249/MK46,M240, T45 Goshawk, just about the entire MRAP line, FMTV, a number of CROWS systems, the 120mm gun on the M1A tanks, Just about all currently used Mortars, 57 and 76mm naval guns, the HK M320 grenade launcher, both the M9/M9A1 and M11 sidearms, HK MP5, MK 13 mod 0, M1014 joint service shotgun Aimpoint M68, Elcan Spectre series optics, Harrier II, and more I can't think of right now All these systems are either directly manufactured in the US from foreign licensed design or built in the US based on a American modification to a foreign design.
both LCS hulls are based of foreign made Civilian ocean going fairy ships but extensively modified for military service.
so if the US wanted to use foreign its possible if they can prove up to the wants of the USN and are willing to License, but in this case I suspect the most likely option would be selection of a of a LCS derived hull.
The two would likely have a lot of commonality, most of the teething issues would have been worked out with the LCS hulls, and the Navy has experience with them.
if I were to pick one I would say the General Dynamics Multi Mission Combatant.
the specs are something like this
127.6m long
31.6m wide
4.4 m Draft
~3120 metric ton
>40 knot top speed
a range of 4500NM in a 16kt cruise
1500nm in a 36kt sprint
11,800 square feet of mission bay
11,100 square foot flight deck
110 man crew accommodations
32vls missiles MK41
1 57mm cannon
8 harpoons
2 phalanx
6 torpedo tubes
2 gas turbines
2 diesels
4 waterjets and retractable azi thrusters
4 diesel generators.
and precisions for Anti mine sonar, mounted M2 HBmg, towed sonar suites
I took those from GD own brochure.
(I believe it was less than 70 hours) and a moment ago a google search didn't give it to me :-( Can you please help me?