I just searched the TAFE sites, they don't use the word "technician" in any formal way there. In fact I'd say "technician" is a very informal term this century; making it theoretically impossible to find a "certified technician".
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Technician \Tech*ni"cian\, n.
a person trained or skilled in the technical details of a
particular art or science, especially one skilled at
operating, maintaining, or repairing equipment, in contrast
to the theory or informational content of a craft; --
formerly also called a {technicist}.
Note: In computer software companies, individuals skilled at
the details of using programs and employed to help
customers to install or use software or troubleshoot
software problems for are also called technicians.
[Webster 1913 Suppl. +PJC]
From WordNet (r) 3.0 (2006) [wn]:
technician
n 1: someone whose occupation involves training in a specific
technical process
2: someone known for high skill in some intellectual or artistic
technique
From Moby Thesaurus II by Grady Ward, 1.0 [moby-thesaurus]:
56 Moby Thesaurus words for "technician":
Admirable Crichton, adept, aficionado, amateur, apprentice,
artificer, artisan, artist, attache, authority, buff, connaisseur,
connoisseur, consultant, cordon bleu, crack shot, craftsman,
craftswoman, critic, dead shot, dilettante, diplomat, diplomatist,
elder statesman, experienced hand, expert, expert consultant, fan,
freak, graduate, handicraftsman, handy man, journeyman, marksman,
master, master carpenter, master craftsman, mechanic, no slouch,
nut, politician, prentice, pro, professional, professor,
proficient, pundit, savant, scholar, shark, sharp, specialist,
statesman, technical adviser, technical expert, wright
"Electrical Engineer" with a degree is probably close enough (even though the degrees don't teach anything relevant to case repair; but hey it's their request). I'd offer to do it but I don't have a ABN/company that would be appropriate.
It would be worth mentioning multiple repair options in a numbered list or table:
(1) Cost of buying another unit and swapping parts (as you mention).
(2) Cost of buying original or reproduction spare parts: infeasible, not available. (as you mention)
(3) Cost of disassembling, removing all decals, bending frame, plugging hole (epoxy?), sanding, painting, re-applying decals, re-assembling, testing and then re-calibrating the unit. Give them units of "estimated technician hours", "estimated technician hourly rate" and then a final cost.
ie you need to give the impression that you're not cherry-picking the information you give them. Also add in a figure of "cost to have packaged this unit in a manner that would have prevented this damage during shipping" to rub it in.
All I can say is "at least it works", but I can see that you're not happy with it arriving different to what you paid for. Apart from aesthetics: it also impacts resale value (use language that insurance & shipping people can understand: "dramatically reduced resale value" and "non-original, damaged condition").