Cebu Pacific used to have tickets to somewhere in Malaysia for 1500 pesos. Maybe you could check for ferry tickets from Julo or Zambo to Malaysia as well. They might look at you like you're an idiot for going to Julo but it meets the requirements.
To get back into Philippines you just need an onward ticket and not necessarily a ticket back to Hong Kong. You can buy a ticket to Kota Kinabalu with Airasia for PHP 1400 with departure around 21 days from today.
Air Asia - Clark (Luzon) - Kota Kinabalu - online around 999 PHP, (ex wednesday march 6-2013) no hidden cost like tiger or Shabu Pathetic
The cool thing I had with Tiger was that my throw away flight was canceled and they automatically credited it back to my debit card. So....I met the outbound ticket requirement and it didn't cost me anything!
Has anyone used the scheme whereby a 'ticket' is rented for 24 hours for $9.99? I want to know if the actual ticket comes into the possession of the hirer or just the itinerary. I ask because I e-mailed a company who provides this service to ask "Can the rented 'ticket' be used to fly out of a country if at an airport's immigration desk entry is refused?". They have not replied to that query. It seems to me that (1) The 'ticket' is actually unusable (even though they say the print out will be obtained from the airline's website) and so what happens if refused entry with an unusable exit 'ticket'? (2) The 'ticket' IS usable to fly - so why don't people rent one of these 'tickets' and use them to go on a trip for only $9.99? The latter is, of course, too good to be true and we know what that means! For $9.99 the renter can choose the exit point but not the destination, however for a 'ticket' from The Philippines there are not likely to be flights to obscure places and so the hirer must end up somewhere acceptable (I think).