Maybe... but it seems that there are no evidence.
The circle of Milton, Lawrence, and Skinner also included Marvell, Oldenburg, and Lady Ranelagh. [...] Henry Oldenburg, a friend of Milton who was later to become Wrst president of the Royal Society (and a friend of Spinoza), had corresponded with Edward Lawrence; drafts of four letters from Oldenburg to Lawrence survive in the archives of the Royal Society: two in French, one in Italian, one in Latin. Similarly, Milton says in a letter to Oldenburg that he has passed on greetings to ‘our Lawrence’.
The friendship with Oldenburg dated from 1653.
Milton studied Dutch and travelled extensively abroad, including Holland, between 1638 and 1639, but this is too early: Spinoza was born in 1632.