This isn't an authentic replica of any helmets that I'm aware of. It looks like it is mixing and matching elements from a couple of actual historical finds, but it isn't clearly rooted in any one surviving helmet. There are other details, such as the brass(?) highlights and the folded eyebrows that give it a look that does not have its place in historical antecedents, but rather modern construction methods that are designed to be more cost effective.

But let's take a look at some actual survivng examples of helmets from the early Middle Ages, both from Scandinavia and England.

This is the Coppergate Helmet Which is from England, around the 8th century

The Gjermundbu Helmet Which is 10th century from Scandinavia.

The Vendel Helmet Which is from the 7th century in Scandinavia

These are the most famous surviving helmets of the "Viking" Age (Loosely defined here as the Vendel and Coppergate helmets are actually from a little before the Viking Age) It seems to me that your particular helmet owes some elements of design to all of them, but is a faithful recreation of none of them.

If you're looking for armor to wear alongside of it, a simple shield and mail coat would complete the outfit that would have been overwhelmingly the most common to find in the period of the Early Middle Ages. on any battlefield by any group of people.