so I recently done 2 more MVM tours (currently tour 28 with 0 australiums) and beside some random items I also got
professional widowmkaker killstreak kit fabricator 

I have most of the robot parts but I do need 2 speclized ks items to craft it im not much trader myself so I dont have lots of refined metal nore keys (currently at 0 keys)  to acquire them easly 

I already did some search and the cheapest one I could fined is 53.33 ref eruka effect 

if anyone of you knows about a cheaper item from what ive found tell me in the comments

thank you and have a nice day