On 5 May 1817, the new organisation and naming of the Landwehr regiments was decided. On mobilisation, the first two battalions two Landwehr regiment each were to combine to form a regiment which took the field.
The 34th Landwehr regiment was to be formed from the
1. Klevisches Landwehr-Regiment (hitherto 6. Westphälisches Landwehr-Infanterie-Regiment)
2. Klevisches Landwehr-Regiment (hitherto 1. Rheinisches Landwehr-Infanterie-Regiment)
The Landwehr cavalry regiments were incorporated into these new Landwehr regiments. The 1. Rheinisches Landwehr-Kavallerie-Regiment (formed in 1815) was split up and distributed to five regiments, amongst them the 1. and 2. Klevisches Landwehr-Regiment.
So very probably Seconde-Lieutenant Schalenkamp ended up in one of the components of the 34. Landwehr-Regiment, which explains the number.
In the first half of 1820, due to the reorganisation of the Landwehr ordered on 22 December 1819, the new 17. Landwehr-Regiment was formed from the the 1. and 2. Klevisches Landwehr-Regiment. The new unit carrying the number 34 was created in Posen (Poznan).
However, the rest of the uniform remains an enigma.
The Rhineland Landwehr had karmoisin (crimson) distinctions and white buttons. The 34th Landwehr cavalry had to have (at least from late 1817) white distinctions and white buttons. This was continued by the 17th Landwehr cavalry in 1819/20.