Actually the 318 is the short block v8 the long is the 360.
The engine is a LA. Better would be to find what the shipping weight would be for a crate and add a couple hundred pounds leeway (yes I know that is a bit extra). you may look on allpar.com as they have a good section on the engines.
Current: 1985 Ramcharger SE Royal / 318 / 2bbl / A727 / 148K
Blue Whale (RIP) - 1987 Ram Van / B250 / 318 / 2bbl / A727 / plow / 193K
White Elephant (RIP) - 1983 Ram Van / B150 / 318 /2bbl / A833 OD4 / 250K - Kept Trans & 36G Tank