For p-code samples, the VB decompiler can be used to get access to its internals. The Lite version is free and provides access to the p-code disassembly, which may be enough for most cases. If the engineer doesn't have enough expertise or time to deal with the p-code syntax, then the paid full version provides a powerful decompiler that produces more readable Visual Basic source code as output:
Another popular option is the P32Dasm tool that allows you to obtain p-code listings in a few clicks:
One of its useful features is its ability to produce MAP files that can later be loaded into OllyDbg or IDA using dedicated plugins. Its documentation also mentions the Visual Basic debugger plugin for IDA, but it doesn't seem to be available to the general public.