Convert from packen [Russia] to tael, tahil [Japan]

Unit Definition (packen [Russia])
The packen is a traditional Russian unit of weight equal to 1200 funte, 30 pudi, 1083 pounds, or 491.4 kilograms.

Unit Definition (tael, tahil [Japan])
The tael, tahil [Japan] is a traditional unit of weight used throughout eastern Asia. During the colonial period, the tael was more or less standardized throughout the region at 4/3 ounce avoirdupois (1/16 catty, 1/12 pound, or about 37.8 grams). In Japan, however, the tael was identified with a slightly smaller traditional unit and is considered equal to 1.323 ounces (37.51 grams). The tael is usually considered equal to the Chinese liang.