I think you had better talk to the people at
Hach? or Ochoa Hogar in Santiago.
La Antillana Comercial has a 35 KW ONAN. It runs about $12,000.
Amaro Motors has used gensets with good service policy. Amaro Motors is a reputible company.
There are people who sell these sets in Miami and Georgia...But 30KW sets are considered "too Little" to be worthy of much attention.
Read the Classifieds in the List?n Diario for other offers.
Regarding the custom built barbeque, let me consult some people. the very best ones use inclined stainless steel or enameled rods. If you PM or email me, I can point you in the right direction.
HB