2002 toyota camry 4 cyl. Seized

I purchased a 2002 toyota camry with 4 cyl. Engine back on
Nov. 30th. It had less than 200,000 miles on it but not too
far from it. Within the three months it ran, I really didn't drive
it much or very far but in mid February I had an accidental
house fire happen bad enough we had to stay at hotel bout
30 miles away. I was driving back to house again on the 3rd
day with both dogs and one decided to pee in my
car...needless to say I was already extremely stressed out
and so i got on the gas a bit...but not very long. Less than
quarter mile. As I was almost to my driveway the car cuts
off..crank it, drove a sec, cuts off again and wouldn't crank
back. After testing alt, batt, cables, and pulleys...a
mechanic friend determined it was indeed locked up when
we couldn't turn the crankshaft pulley.  My question is
one..is there anything I can do to possibly unlock it and if
not, two, is there any v6 3.0L engines that would work as a
replacement? (I've always my v6 cars last a long long time)
Or if not, three what is my cheapest, yet long lasting
options??? Please help!!