Help with moped conversion Please!

[Nate]

Im looking to convert a Batavus hs50

   

I want 45 - 50 mph top speed
Range of 25 - 35 miles
I was looking at the EMC-R kit for around 1100$ but that would only leave me about 400 for batteries and I would like Lithium ion
I was also thinking about a Delta wye x5 hub motor since the moped with the engine will only weigh around 70 lbs
What other kits are offered and can meet my specifications
What are the 101 options for lithium and what will I get out of it for each kit
Has anyone seen or done a dirt jumper bicycle motorcycle conversion?
Thanks any help is welcomed

[LeadFoot]

Nice looking old bike!

I'd be careful going 50 mph on it though - those brakes look small for that speed.