What is the proper size of a sqlite database of 4 primary keys if I need fast query speed?

I have a sqlite database for map storage. The table is like this:

(x,y,zoom,type,image) 

Where

(x,y,zoom,type)

is a combined primary key. I would like to know the max size(rows) I could get for this database so that if I query for one image the query time is less than 100ms. I am working on a intel I5 modern laptop.