I'm doing exactly this, but in a more-complicated-than-necessary way, since I setup my profiles before certain states within Tasker were available. Here's what I would do now.
Let's say you want calls from home and from work to ring using the ringer at maximum volume, regardless of the current settings. Let's also say that your home number is 8005551212 and your work number is 8665551234. Here's the profile you would setup:
Profile: Priority Caller
Context: Incoming Call [Caller Number: 8005551212/8665551234]
Enter Task Action: Silent Mode [Mode: Off]
Enter Task Action: Ringer Volume [Level: 7]
Enter Task Action: Vibrate on Ringer [Set: On]
When a call comes in from either number, Tasker will turn off silent mode, maximize the ringer volume, and make the phone vibrate when it rings. Once the phone stops ringing (i.e. you answer or miss the call), these settings are returned to their pre-call values.
Mine is a little more complicated (not just due to the capabilities of Tasker when I set it up). My profile gradually increases the ringer volume every few seconds, starting at 3, then 5, then 7. This gives me a chance to answer the call before the ringer gets too intrusive.