Heuschrecke 10
Waffenträger (Weapon Carrier)
http://www.achtungpanzer.com/wafft.htm#heu
Sd.Kfz.165/1
"based on modified Panzerkampfwagen IV's chassis (Sd.Kfz.161). Modified chassis consisted of three-station bogies per side and larger road wheels."
http://www.achtungpanzer.com/wafft.htm#sd165
10.5cm K18 auf Panzer Selbstfahrlafette IVa
"Dickermax"
http://www.achtungpanzer.com/sel105.htm#pzjag
12.8cm Selbstfahrlafette L/61
(Panzerselbstfahrlafette V)
"Sturer Emil / Stubborn Emil"
http://www.achtungpanzer.com/heu.htm#128
So these are all different vehicles. Although very similar.