"get a slice of" is correct and usable in written English.
You can use it to refer to a metaphorical or literal slice of something, usually food (e.g. "Let's get a slice of pizza").
Everyone is trying to get a slice of the action.
They can get a slice of pizza for $3.
But now a rival is trying to get a slice of the aerospace pie.
The BBC is to get a slice of the profits, if there ever are any.
"There can be a multitude of cronies squabbling to get a slice of the cake".
For who doesn't want to get a slice of a multi-billion-dollar pie?
And maybe I will get a slice of that pumpkin loaf.
In recent years, they've gone Republican, but this year the Democrats could get a slice of them".
In some cases, TV makers also get a slice of the revenue when customers make Web purchases from their TVs.
I can give my kids money to get their haircut by themselves and get a slice of pizza.
Tech companies do offer ways to get a slice of your data without invoking the Data Protection Act.
