According to [1], taking a 40yr old male, the body would be 180cm x 25cm x 70cm (805, 236, 506+378 extrapolated). You'd probably want at least 2.5cm of epoxy border giving you 185cm x 30cm x 75cm or 0.42m^3. Assuming the body takes up about 0.067m^3[2], you're left with 0.35m^3 or 21350in^3. [3] says multiply that by 0.0163 to get 350 litres which then translates to kg of resin. Using GlassCast 50, at 32kg for £450 inc vat, you'd be looking at ~£4900.

(you could also just paint over a few thin layers instead but it wouldn't look as impressive.)

(also you'd need to dry the body out first because the resin would react badly with the moisture.)

[1] https://msis.jsc.nasa.gov/sections/section03.htm [2] https://www.researchgate.net/post/Volume_of_average_human_bo... [3] https://www.easycomposites.co.uk/#!/resin-gel-silicone-adhes...