For is often used after the verb size, without changing the meaning of the expression.
The tables of the Undergraduates, arranged according to their respective years, are supplied with abundance of plain joints, and vegetables, and beer and ale ad libitum, besides which, soup, pastry, and cheese can be "sized for," that is, brought in portions to individuals at an extra charge.—Bristed's Five Years in an Eng. Univ., Ed. 2d, p. 19.
To size upon another. To order extra food, and without permission charge it to another's account.
If any one shall size upon another, he shall be fined a Shilling, and pay the Damage; and every Freshman sent [for victuals] must declare that he who sends him is the only Person to be charged.—Laws Yale Coll., 1774, p. 10.
SIZING. Extra food or drink ordered from the buttery; the act of ordering extra food or drink from the buttery.
Dr. Holyoke, who graduated at Harvard College in 1746, says: "The breakfast was two sizings of bread and a cue of beer." Judge Wingate, who graduated a little later, says: "We were allowed at dinner a cue of beer, which was a half-pint, and a sizing of bread, which I cannot describe to you. It was quite sufficient for one dinner."—Peirce's Hist. Harv. Univ., p. 219.
From more definite accounts it would seem that a sizing of biscuit was one biscuit, and a sizing of cracker, two crackers. A certain amount of food was allowed to each mess, and if any person wanted more than the allowance, it was the custom to tell the waiter to bring a sizing of whatever was wished, provided it was obtained from the commons kitchen; for this payment was made at the close of the term. A sizing of cheese was nearly an ounce, and a sizing of cider varied from a half-pint to a pint and a half.
The Steward shall, at the close of every quarter, immediately fill up the columns of commons and sizings, and shall deliver the bill, &c.—Laws Harv. Coll., 1798, p. 58.
The Butler shall frequently inspect his book of sizings.—Ibid., p. 62.
Whereas young scholars, to the dishonor of God, hinderance of their studies, and damage of their friends' estate, inconsiderately and intemperately are ready to abuse their liberty of sizing besides their commons; therefore the Steward shall in no case permit any students whatever, under the degree of Masters of Arts, or Fellows, to expend or be provided for themselves or any townsmen any extraordinary commons, unless by the allowance of the President, &c., or in case of sickness.—Orders written 28th March, 1650.—Quincy's Hist. Harv. Univ., Vol. I. p. 583.