[Eljaro]

Andronikos,
sorry to read your bad experience. You think you have a nice cobra and you want to drive it and enjoy, and all of a sudden you find yourself with a broken engine.
Something very similar happened to me on my first excursion with my new cobra. I did not get very far because the headgasket blew and the engine went hidro. Hade to send the engine twice to England to have it repaired by the guy who build it (badly), and the third time I had a problem I decided to do it myself.
Get yourself a Haynes manual for your engine, get a torque wrench, take the engine out of the car (you will have to eventually) and have the crankshaft repaired locally.
I live in Mallorca, Spain, and here we have many mechanics servicing boat engines, most of them are big american V8. So the experience is there. I am sure that there is some shop doing crankshaft turning and polishing. You can take the engine block to such a shop and they will repair it. You will only have to get them the rod and main bearings, they will do the rest. The Haynes manual will tell them the tolerances and torque values.
Get an ARP shaft for the pump, or any other real good shaft.
Your rockers are sitting to low on rocker stud. The rocker studs are probably too short Check the manufacturer of the rockers and see if some longer rocker studs are on offer. You will also need longer pushrods. Two or three of the hydraulic lifters will have to be replaced too.
You can get parts at Summit or Jegs or any other of the online automotive shops.
You can also contact someone like Keithcraft and have him have a look at the pictures. He can tell you what you need to fix the valvetrain issue.
I would take the engine out, remove the heads, check the valves for bent ones, take the engine block to a machine shop for crankshaft repair and in the meantime sort the valve train issue.
You can also order a new short block , but you will have to pay over 2000$ for freight,, plus custom tax and the 23% VAT tax. Expensive.
Do it youself, you will learn a lot and eventually enjoy working on the car as much as driving it.
By the way, what Cobra is that? Looks like the front suspension from a BMW Series 3.