"small premium" is correct and can be used in written English.
For example: "You can get a low-cost insurance plan if you are willing to pay a small premium."
"In such a way they don't mind paying a small premium for a better experience".
People might be willing to pay a small premium for real food.
The Sony Z1 Compact is the first of a new generation of small, premium Android phones.
Each offer represents a small premium to the Monday closing prices.
Over a year it has returned 32% and has a small premium of 2.2%.
As prices stood in the final week, BNP's hostile offers represented a small premium over the other options.
In the academic literature, some researchers focusing on salaries have found a small premium for state and local workers.
Medicare also requires a small premium, which virtually every eligible person pays, for services other than hospital stays.
Indeed, several media industry executives said they thought that Comcast might have miscalculated in offering a relatively small premium.
Or even for the small "premium plus" payment Hulu is now offering for earlier airings of hit shows?
Before the housing crisis, Fannie and Freddie could borrow money at a small premium over the federal government's rates.
