How hard is it to get trophies back to the US? Can one bring smaller trophies back in their luggage with vet certificates or a boiled skull?
I will tell you what I did, but would strongly recommend that you check well before you depart for the hunt, as the regulations have apparently changed over the past several years and will likely continue to evolve. Note that the importation of trophies involves both the Customs office and the USFWS, so there are two sets of regulations through which you must navigate, and two sets of inspections which have to take place.
In my case (importing in 2019) it required the following:
1. A "Proforma Invoice" describing the "goods to be imported" (i.e., red stag hunting trophy) and quantity (one). The outfitter (Horia) provided this.
2. A "Declaration of Origin" which stated that the animal was legally taken, the country of origin, and that the taxidermy had been performed on it prior to shipment. The document was signed by the local "Ranger" (game warden) and was then forwarded by the outfitter (Horia).
3. Another document "Valea Ramnicului" which I frankly don't understand but appears to have something to do with the declared value of the trophy. This was also provided by the outfitter (Horia).
For the stag, there was also a Bill of Lading from the air-freight company, since my Red Stag was obviously too big to fit in the overhead compartment of the airplane and had to be shipped separately.
We looked for a long time for an air freight company which would not charge an arm & a leg, and finally settled on LOT Polish Airways Freight, operating from Bucharest Airport. They charge less than 1/3 of what we were quoted by the big-boys such as FEDEX and DHL.
I opted to use a Customs Broker, which turned out to be a good call, as they were able to shepherd the cargo through the Customs and USFWS inspection processes and then forward it on to me. They also temporarily stored the crate in their bonded warehouse for about a week while we awaited additional paperwork and the inspectors' schedules. That helped me avoid some fairly hefty storage charges compared to becoming "frustrated cargo" in the Customs warehouse. Horia and I received quite an education on the import requirements, as our system here is much more complicated than shipping to other countries in Europe, and none of the brokers with whom I spoke seem to be familiar with Romania as a hunting destination. We struggled a bit to obtain all the necessary documents, but once the shipment arrived in a US Port of Entry and the Customs Broker took over, things moved pretty quickly. Money well spent, in my opinion. I used Coppersmith Logistics, but there are others out there.