Is "scopperloit" a real word?

Yes, it’s a “real word”, whatever that is supposed to mean. The OED says it is dialectal, rather than obsolete. Per the OED, scopperloit is play that is romping, rude, indelicate in nature. It seems to correspond to words like horseplay or roughhousing in contemporary English.

ˈscopperloit. dial.

Also 7 skoppoloit, -lot.

Etymology: Of obscure origin: cf. scobberlotcher and scoterlope v.

(See quots.)

• 1691 Ray S. & E.C. Wds. 111 ― A Scopperloit, a time of idleness, a play-time.
• 1787 in Grose Prov. Gloss.
• 1878 S. H. Miller & Skertchly Fenland iv. 131 ― Skoppolot, Skoppoloit, romping, rude, indelicate play.

I couldn't find a definition for this obsolete word in any online dictionary. However, a li'l digging unearthed the following references in a couple of esoteric catalogues:

From The Routledge Dictionary of Historical Slang (1973):

... the North Country and East Anglian scopperloit, soppoloit, a time of idleness or of play ...

From An Universal Etymological Dictionary (1759):

A Scopperloit, a Time of Idleness, a Play-Time.

It also finds mention in an investigation of the word scobberlotcher:

The Oxford English Dictionary points, tentatively, to two old words as possible antecedents. One is the eastern English regional scopperloit, a time of idleness (perhaps from Dutch leuteren, to idle, the source of English loiter).

A few hits on Google such as this one go a step further by claiming that scopperloit can also mean "rude and rough-housing play". I couldn't find any sources to corroborate this nuance. (Edit: tchrist's answer confirms that the OED includes this additional definition.)