Nearest to the 'core' I would recommend Amadeu's in Kensington Market. Probably the closest Portuguese place you will find.
If you are willing to travel a little farther, go around College/Dovercourt to Bairrada Churrasqueira. I prefer the place in the summer; really nice patio in the back.
My recommendations for Portuguese cuisine: shrimp rissóis and bacalhau pastéis, bifana sandwiches, feijoada, grilled sardines, octopus stew and bacalhau à gomes de sá. Just a few of my personal favorites.
Only Portuguese place I've been to is Adega on Elm Street near Bay. With nothing else to compare it to, I enjoyed it. Everything from the service, food and decor was simply good.
The menu is not elobrate and dishes are simple but cleverly and nicely paired. Most memorable was their dessert and the wine cellar/list.
As much as I love Chiado, it is not a "reasonably priced place" by any stretch of the imagination. Hell, you really can't even get a bottle of portuguese wine there for under $70. Even the tapas bar inside Chiado (Senhor Antonio) will run you about $150 for two people with wine for dinner.
The menu is on the website: http://www.chiadorestaurant.ca/