Good spotting Ted

Would definitely be a nice aussie block

I checked a parts catalogue (which reminds me I have to upload a few old ones I found) and the 505 had what could be described as a standard wide 'commando' type cowl - sans internal tank

https://webarchive.nla.gov.au/awa/20040915105630/http://pandora.nla.gov.au/pan/24350/20020520-0000/www.victa.com.au/index563e.html

This is the old victa website from 2004 - surprisingly for a Hi-po model, it only has the small snorkel