The bank entry is wrong, because the surplus is for revaluation and gain cannot be classified as surplus. When you dispose the asset any revaluation surplus is transferred to revenue reserves called retained earnings. Even in indas all the revaluation gain is transferred to retained earnings. So the terminology differs and so
Asset is 100 revalued to 200
Dr. Asset 100
Cr. Surplus 100
And transfer the surplus to revaluation reserve
Dr. Surplus
Cr. Reserves account
When you sell the same asset for 200
Dr. Bank 200
Cr. Asset 100
Cr. Gain on sale 100.
There is no law apart from section 129 which clearly says surplus comes from sales apart from the depreciation surplus. On disposal existing surplus from reserves will be transferred to retained earnings and some surplus part related to cost and revaluation depreciation will be transferred to surplus account.