Hello,
Hello,
I agree with what has been said here.
---Your Bavarian plate is an M1896 for the line infantry. On the photo, the M1886 (the largest) and the M1914 (the medium), were among others for officers, but rather with all openwork crowns.
---Yes, this is a mobilisation helmet, (old leather bomb, but with visor and neck-cover in vulkanised fibre (thin and black).
The hexagonal nut under the neck-cover is period fitted on mobilisation helmets, Ersatz, in sheet metal, etc...
---Lastly, you have to look at the quality/price ratio. The schell is in good condition, the Landwehr-kreuz is missing, but a Bavarian active service plate is easy to find. On the other hand, as mentioned above, you shouldn't spend more than 300€ on this helmet, because in France, a Bavarian nickel silver cocade costs 100€, a Reichskokarde 80€, and a brass-trimmed chinstrap, 200€. These are items that are very often missing and very much in demand.